Coupling device



April 2, 1968 S M wlLLEY ET AL 3,375,543

COUPLING DEVICE Filed Aug. 13, 1965 2 Sheets-Sheet l 3Q /\`T V195 CiZlQO ISGINVEHTORS.

SALLY MARGARET vV/LLEY RONALD VICTOR TEBBUTT Apri 2, i968 s. M. WILLEY ET AL 3,375,543

couPLING DEVICE Filed Aug. l5, 1965 2 Sheets-Sheet 2 INVENTOQS. SALLY MADC-5A PET VV/LLEY QONALD VlcTon TEBBUTT BY l.

ATTOR NEY.

United States Patent 3,375,543 COUPLING DEVICE Sally Margaret Willey and Ronald Victor Tebbutt, London, England, assignors to Schema Limited, London, England, a British company Filed Aug. 13, 1965. Ser. No. 479,524 Claims. (Cl. 16-139) ABSTRACT 0F THE DISCLDSURE A hinge for doors and the like which is self-stabilizing in one or more positions. Includes resilient displaceable hook elements movable relative `to stationary members so that the movable member to be attached to a door or table leg, for example, becomes relatively fixed and immovable at predetermined positions.

This invention relates to a coupling and more specifically to a coupling which iS self-stabilising in one or more positions.

It has for some time been a desirable feature of a hinge that the respective moving members should be arrested at certain points in their movement, for example, when applied to -a door of a cupboard, a car or a house where it is desired to prevent the door from swinging shut of its own accord. Hitherto, such hinges have included friction or ratchet means to damp ther action or, more often, a device further to the hinge is provided to govern the action of 4the hinge or arrest the door in certain positions, such devices usually comprising a pivoted arm mounted between the door and the door frame.

Further, there has been an increasing demand for a coupling for application to folding tables, chairs, steps and like foldable articles where it is necessary to lock an element of the article in or out of a folded position. ln the case of a folding card table, for example, it is desirable that the legs should be rigidly mounted and secure so that they will not collapse when the table is in normal use and will be firmly secured in a folded away position when not in use. Hitherto, such coupling devices have included various and often complicated fixing means more often not actually being comprised as part of the coupling itself. Such devices are relatively expensive and complicated items which add both tothe cost of the article and to its overall weight.

This invention provides a coupling which may be used in place of a hinge for light weight doors such as cupboard doors and the like: as a coupling member in conjunction with a hinge to act as an arresting means on a relatively heavy door such, for example, as a car door or the door of a refrigerator; as means for coupling one element to another element of an article of folding furniture or the like, for example, a leg to a table, to couple a pair of steps or to hinge the lid of a radiogramme. Further uses and features of the coupling of the invention will become apparent upon disclosure of the invention in the following description.

The coupling device of the invention comprises a first member provided with one or more resiliently displaceable hook portions, a second member provided with one or more pivot pieces to engage the hook portions in a manner such that one member is movable in its engagement with respect to the other member, a heel on the second member disposed to cause displacement of the hook portions on the rotation of the second member with respect to the first, one or more flat faces on the second member, each face meeting with a fiat face of the first member in a position of stable equilibrium of the device.

The resiliently displaceable hook portions are preferably integral with and of the Same material as the first member. The pivot pieces may be integral with and of the same material as the second member. Alternatively the pivot pieces may comprise part of a shaft which is suitably mounted on the second member so that the hook portions may pivot about it.

The hook portions preferably form part-circular recesses into which the pivot pieces, preferably of similar diameter circular cross-section, of the second member may be introduced through a gap formed between the face of the first member and the nose of a hook portion. By the resilient nature of the hook this may be achieved by pressing the pivot pieces of the first member through the gap or gaps to engage the hook thus engaging the two members.

The resiliently displaceable hook portions are preferably made of materials such, for example as nylon, polypropylene, a rigid polythene known under the registered trademark Rigidex or any other suitable plastics material having similar displaceable resilient properties of the above mentioned examples. Conveniently, both the first and second members of the coupling of the invention may be made of the above said materials which are relatively inexpensive and readily formable integrally to include all the essential components of each member.

The faces of the second member are preferably disposed tangentially of the pivot pieces and a heel is formed between them. The heel projects at right angles from the axis of the pivot pieces and is preferably formed at the point where two faces meet at an angle about the pivot pieces, the radius of the heel from the axis of the pivot pieces being somewhat greater than the radius of the pivot pieces themselves.

The second member may be provided with a rounded face concentric with the pivot portions and in addition to at least one flat face. The rounded face provides a degree of rotation of one member in relation to the other which rotation is not subject to the influence of the stabilizing factor. Instead, the relative movement of the two members is somewhat damped by friction which occurs between the rounded face and the face of the first member and is enhanced by the resilient nature of the hook portions causing the faces more firmly frictionally to engage.

Both the first and second members are preferably provided with means whereby they may securely be mounted lto respective structural elements, said means comprising for example screw holes or threaded sockets to receive a bolt.

It has been found to be a further advantage of the nvention, particularly when the coupling is applied to the fixing of folding legs to a table, to provide a positive locking means releasable manually whereby the device may be locked in one of its positions of stable equilibrium. Such locking means may comprise a simple ratchet clip provided by projections on one member which are eugageable -with further projections on the other member.

Two preferred embodiments of the coupling of the invention will hereinafter be described with reference to the accompanying drawings in which FIGURE l is a front perspective View of a coupling having two positions of stable equilibrium and shown in the first of those positions.

FIGURE 2 is a perspective view of the coupling in FIG- URE 1 but shownin the second position of stable equilibrium.

FIGURE 3 is a rear perspective of the coupling in FIGURES l and 2 shown in the second position of equilibrium.

FIGURE 4 is a front elevation of the locking means of the coupling shown in FIGURES 1 to 3.

FIGURE is a perspective view of a second form of coupling according to the invention having only one position of stable equilibrium.

FIGURE 6 is an exploded view of the coupling shown in FIGURE 5.

Referring to FIGURES 1 to 4, a first member 1 comprises a single moulding of polypropylene plastics material, and is formed with a pair of hooks 2 one at each side of and projecting upwardly from a face 3, Screw anchoring holes 4 are provided in the first member 1. A second member 5 is made of the same material as the first member 1 is formed with a central body 6 provided with two co-axi-al pivot pieces 7 at opposite sides of the central body 6 so as to engage in the hooks 2 of the first member 1. The central body 6 has two faces 8 (FIGURE 1) and 9 (FIGURE 3) which respectively meet co-planar with the face 3 of the first member 1 in one of the two positions of relative stable equilibrium of the device. A heel 10 is formed at the angle where the two faces 8 and 9 meet, this heel being co-linear with but radially disposed to the axis I-I of the pivot pieces 7. The heel 10 engages the face 3 when the member 5 is partially rotated about the axis I-I in the direction ot the arrows shown respectively in FIGURES 1 to 3, and the hooks 2 are resiliently displaced upwardly.

A projection 11 threaded at 11a is provided on the top of the body 6 whereby a table leg or like element may be secured by screwing to the second member 5. A trunoated projection 12 extends from one side of the body 6 to engage as a ratchet a cut out portion 13 in the first member 1. As seen in FIGURE 4, the projection 12 is bifurcated to define two resiliently displaceable legs 12a each with an outwardly extending .foot 12b to engage an extended portion of member 1 in which there is provided the notch or cutout portion y13. Each of the sides 13a which form the notch 13 has its inner edge tapered as at 13b to resiliently displace the legs -12a as these enter the notch portion 13. When the feet 12b have passed over the tapered portion 13b they resiliently engage upon a second contra-tapered portion 13C and are not withdrawable except by very considerable force exerted upwardly or by pinching the legs 12a together.

FIGURES 5 and 6 show a coupling having a first member 21 provided with resilient hooks 22, a tace 23 and mounting screw holes 24, a second member 25 having a body 26 with co-axial two pivot pieces 27 at each side to engage the hooks 22. The body 26 is provided with a at face 28 (FIGURE 6) and a rounded face 29. The flat face 28 meets the face 23 of the first member 21 and the two members are then maintained in relative stable equilibrium through the resilient action of the hooks 22 on the pivot pieces 27. A heel 30 is formed Where the faces 28 and 29 meet and this heel is frictionally brought to bear on the face 23 of the first member 21 when one member is moved in part rotation with respect to the other member. The hooks 22 are then resiliently displaced and the rounded face 29 frictionally bears on the face 23 and the two members may then be moved in relative part rotation, the face 29 bearing on the face 23, comparatively free from any stabilizing influence, the hooks 22 remaining resiliently displaced until the members are moved back to their position of stable equilibrium.

In the foregoing examples of the coupling of the 1nvention it will be understood that the means for mounting the coupling to a structural element may be varied according to the particular application for which the coupling is used.

The coupling device of the invention operates as follows. When the two members are in a relative position of stable equilibrium the resilient hooks 2 of the first member 1 press down upon the pivot pieces 7 of the second member 5 in a manner firmly to meet one face of the second member with the face 3 of the first member so that the meeting faces form a stable association of the two members. If the second member 5 is partially rotated with respect to the first member 1 the heel 10 0n the second member 5 engages the face 3 of the first member 1 as a level to displace the resilient hooks 2, thel pivot pieces providing the fulcrum. The two members then tend to maintain their original position of stable equilibrium urged by the resilience ofthe hooks 2 until the heel 10 passes through a point determined by a vertical line passing at right angles from the face of the first element through the axis I-I of the pivot lpieces 7.

Beyond this point the two members will tend to assume a second position of relative stable equilibrium if the second member S is provided with further flat face or, will reach a state of relative neutral stability if the second member is provided with a rounded face 24 (FIGURES 5 and 6) concentric with the pivot pieces 27. In the case where the second position of stable equilibrium is reached the hooks 2 resiliently return to their original form. In`

the case where there is a rounded face (see FIGURES `5 and 6) the hooks 22 remain resiliently displaced and` serve frictionally to engage the rounded face 24 of the second member with the face 23 of the first member 21. until the members are moved back to a position of stable equilibrium.

We claim:

1. A coupling comprising a first member, at least one resiliently displaceable -hook portion on said first member, a second member, at least one pivot piece on said second member in engagement with said hook portion, said first member movable in engagement with respect to said second member, at least one at face on said first member, at least one flat face on said second member, at least one heel on said second member, an extended portion on said first member, a truncated projection on said second member, said at face on the lrst member meeting adjacent said fiat face on the second member in at least one position of stable equilibrium of the coupling, and said truncated projection lockably engageable with said extended portion in said extended portion in said position.

2. A coupling according to claim 1 in which said extended portion is provided with a notch, said truncated projection having a bifurcated end portion definingsubstantially parallel spaced apart resiliently displaceable legs, a laterally extended foot on eachileg extending in respective opposite directions to each other, and said feet being engageable with the opposed edges of said notch.

3. A coupling according to `claim 2 in which the op posed edges defining said notch are parallel, the facesof said edges rbeing angled convergently with respect to one another, and said feet cooperating with said faces in seel References Cited UNITED STATES PATENTS 2,677,479 5/1954 Kitba 16-172 2,874,401 2/1959 Kotkins 16-145 FOREIGN PATENTS 963.023 12/1949 France.

BOBBY R. GAY, Primary Examiner.

D. L. TROUTMAN, A ssstant Examiner. 

